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class="post-meta-separator">|</span><i class="fas fa-inbox fa-fw post-meta-icon"></i><a class="post-meta-categories" href="/blog/categories/RxSwift/">RxSwift</a></span></div><div class="meta-secondline"><span class="post-meta-separator">|</span><span class="post-meta-wordcount"><i class="far fa-file-word fa-fw post-meta-icon"></i><span class="post-meta-label">字数总计:</span><span class="word-count">1.1k</span><span class="post-meta-separator">|</span><i class="far fa-clock fa-fw post-meta-icon"></i><span class="post-meta-label">阅读时长:</span><span>4分钟</span></span><span class="post-meta-separator">|</span><span class="post-meta-pv-cv" id="" data-flag-title="RxSwift的使用详解9-过滤操作符"><i class="far fa-eye fa-fw post-meta-icon"></i><span class="post-meta-label">阅读量:</span><span id="busuanzi_value_page_pv"></span></span></div></div></div></header><main class="layout" id="content-inner"><div id="post"><article class="post-content" id="article-container"><h2 id="九、过滤操作符（Filtering-Observables）"><a href="#九、过滤操作符（Filtering-Observables）" class="headerlink" title="九、过滤操作符（Filtering Observables）"></a>九、过滤操作符（Filtering Observables）</h2><p>过滤操作指的是从源 <strong>Observable</strong> 中选择特定的数据发送。</p>
<h3 id="1，filter"><a href="#1，filter" class="headerlink" title="1，filter"></a>1，filter</h3><p>（1）基本介绍</p>
<ul>
<li>该操作符就是用来过滤掉某些不符合要求的事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011410313958618.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">2</span>, <span class="number">30</span>, <span class="number">22</span>, <span class="number">5</span>, <span class="number">60</span>, <span class="number">3</span>, <span class="number">40</span> ,<span class="number">9</span>)</span><br><span class="line">    .filter &#123;</span><br><span class="line">        <span class="variable">$0</span> <span class="operator">&gt;</span> <span class="number">10</span></span><br><span class="line">    &#125;</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011410344030076.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="2，distinctUntilChanged"><a href="#2，distinctUntilChanged" class="headerlink" title="2，distinctUntilChanged"></a>2，distinctUntilChanged</h3><p>（1）基本介绍</p>
<ul>
<li>该操作符用于过滤掉连续重复的事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011410432018816.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">4</span>)</span><br><span class="line">    .distinctUntilChanged()</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011410461730683.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="3，single"><a href="#3，single" class="headerlink" title="3，single"></a>3，single</h3><p>（1）基本介绍</p>
<ul>
<li>限制只发送一次事件，或者满足条件的第一个事件。</li>
<li>如果存在有多个事件或者没有事件都会发出一个 <strong>error</strong> 事件。</li>
<li>如果只有一个事件，则不会发出 <strong>error</strong> 事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011610392767099.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .single&#123; <span class="variable">$0</span> <span class="operator">==</span> <span class="number">2</span> &#125;</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="string">&quot;A&quot;</span>, <span class="string">&quot;B&quot;</span>, <span class="string">&quot;C&quot;</span>, <span class="string">&quot;D&quot;</span>)</span><br><span class="line">    .single()</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011610423482299.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="4，elementAt"><a href="#4，elementAt" class="headerlink" title="4，elementAt"></a>4，elementAt</h3><p>（1）基本介绍</p>
<ul>
<li>该方法实现只处理在指定位置的事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011410594284689.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .elementAt(<span class="number">2</span>)</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011411012335623.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="5，ignoreElements"><a href="#5，ignoreElements" class="headerlink" title="5，ignoreElements"></a>5，ignoreElements</h3><p>（1）基本介绍</p>
<ul>
<li>该操作符可以忽略掉所有的元素，只发出 <strong>error</strong> 或 <strong>completed</strong> 事件。</li>
<li>如果我们并不关心 <strong>Observable</strong> 的任何元素，只想知道 <strong>Observable</strong> 在什么时候终止，那就可以使用 <strong>ignoreElements</strong> 操作符。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018012910235142738.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .ignoreElements()</span><br><span class="line">    .subscribe&#123;</span><br><span class="line">        <span class="built_in">print</span>(<span class="variable">$0</span>)</span><br><span class="line">    &#125;</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018012910272769797.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="6，take"><a href="#6，take" class="headerlink" title="6，take"></a>6，take</h3><p>（1）基本介绍</p>
<ul>
<li>该方法实现仅发送 <strong>Observable</strong> 序列中的前 <strong>n</strong> 个事件，在满足数量之后会自动 <strong>.completed</strong>。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/201801141104142132.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .take(<span class="number">2</span>)</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011411054285142.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="7，takeLast"><a href="#7，takeLast" class="headerlink" title="7，takeLast"></a>7，takeLast</h3><p>（1）基本介绍</p>
<ul>
<li>该方法实现仅发送 <strong>Observable</strong> 序列中的后 <strong>n</strong> 个事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/201801141111165051.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .takeLast(<span class="number">1</span>)</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/201801141113168979.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="8，skip"><a href="#8，skip" class="headerlink" title="8，skip"></a>8，skip</h3><p>（1）基本介绍</p>
<ul>
<li>该方法用于跳过源 <strong>Observable</strong> 序列发出的前 <strong>n</strong> 个事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011609031868903.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="type">Observable</span>.of(<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>)</span><br><span class="line">    .skip(<span class="number">2</span>)</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011609054130768.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="9，Sample"><a href="#9，Sample" class="headerlink" title="9，Sample"></a>9，Sample</h3><p>（1）基本介绍</p>
<ul>
<li><strong>Sample</strong> 除了订阅源 <strong>Observable</strong> 外，还可以监视另外一个 <strong>Observable</strong>， 即 <strong>notifier</strong> 。</li>
<li>每当收到 <strong>notifier</strong> 事件，就会从源序列取一个最新的事件并发送。而如果两次 <strong>notifier</strong> 事件之间没有源序列的事件，则不发送值。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/201801161024167794.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line"> </span><br><span class="line"><span class="keyword">let</span> source <span class="operator">=</span> <span class="type">PublishSubject</span>&lt;<span class="type">Int</span>&gt;()</span><br><span class="line"><span class="keyword">let</span> notifier <span class="operator">=</span> <span class="type">PublishSubject</span>&lt;<span class="type">String</span>&gt;()</span><br><span class="line"> </span><br><span class="line">source</span><br><span class="line">    .sample(notifier)</span><br><span class="line">    .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">    .disposed(by: disposeBag)</span><br><span class="line"> </span><br><span class="line">source.onNext(<span class="number">1</span>)</span><br><span class="line"> </span><br><span class="line"><span class="comment">//让源序列接收接收消息</span></span><br><span class="line">notifier.onNext(<span class="string">&quot;A&quot;</span>)</span><br><span class="line"> </span><br><span class="line">source.onNext(<span class="number">2</span>)</span><br><span class="line"> </span><br><span class="line"><span class="comment">//让源序列接收接收消息</span></span><br><span class="line">notifier.onNext(<span class="string">&quot;B&quot;</span>)</span><br><span class="line">notifier.onNext(<span class="string">&quot;C&quot;</span>)</span><br><span class="line"> </span><br><span class="line">source.onNext(<span class="number">3</span>)</span><br><span class="line">source.onNext(<span class="number">4</span>)</span><br><span class="line"> </span><br><span class="line"><span class="comment">//让源序列接收接收消息</span></span><br><span class="line">notifier.onNext(<span class="string">&quot;D&quot;</span>)</span><br><span class="line"> </span><br><span class="line">source.onNext(<span class="number">5</span>)</span><br><span class="line"> </span><br><span class="line"><span class="comment">//让源序列接收接收消息</span></span><br><span class="line">notifier.onCompleted()</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018011610300334312.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<h3 id="10，debounce"><a href="#10，debounce" class="headerlink" title="10，debounce"></a>10，debounce</h3><p>（1）基本介绍</p>
<ul>
<li><strong>debounce</strong> 操作符可以用来过滤掉高频产生的元素，它只会发出这种元素：该元素产生后，一段时间内没有新元素产生。</li>
<li>换句话说就是，队列中的元素如果和下一个元素的间隔小于了指定的时间间隔，那么这个元素将被过滤掉。</li>
<li><strong>debounce</strong> 常用在用户输入的时候，不需要每个字母敲进去都发送一个事件，而是稍等一下取最后一个事件。</li>
</ul>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018012619463746521.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
<p>（2）使用样例</p>
<figure class="highlight swift"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br></pre></td><td class="code"><pre><span class="line"><span class="keyword">import</span> UIKit</span><br><span class="line"><span class="keyword">import</span> RxSwift</span><br><span class="line"><span class="keyword">import</span> RxCocoa</span><br><span class="line"> </span><br><span class="line"><span class="keyword">class</span> <span class="title class_">ViewController</span>: <span class="title class_">UIViewController</span> &#123;</span><br><span class="line">     </span><br><span class="line">    <span class="keyword">let</span> disposeBag <span class="operator">=</span> <span class="type">DisposeBag</span>()</span><br><span class="line">     </span><br><span class="line">    <span class="keyword">override</span> <span class="keyword">func</span> <span class="title function_">viewDidLoad</span>() &#123;</span><br><span class="line"> </span><br><span class="line">        <span class="comment">//定义好每个事件里的值以及发送的时间</span></span><br><span class="line">        <span class="keyword">let</span> times <span class="operator">=</span> [</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">1</span>, <span class="string">&quot;time&quot;</span>: <span class="number">0.1</span> ],</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">2</span>, <span class="string">&quot;time&quot;</span>: <span class="number">1.1</span> ],</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">3</span>, <span class="string">&quot;time&quot;</span>: <span class="number">1.2</span> ],</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">4</span>, <span class="string">&quot;time&quot;</span>: <span class="number">1.2</span> ],</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">5</span>, <span class="string">&quot;time&quot;</span>: <span class="number">1.4</span> ],</span><br><span class="line">            [ <span class="string">&quot;value&quot;</span>: <span class="number">6</span>, <span class="string">&quot;time&quot;</span>: <span class="number">2.1</span> ]</span><br><span class="line">        ]</span><br><span class="line">         </span><br><span class="line">        <span class="comment">//生成对应的 Observable 序列并订阅</span></span><br><span class="line">        <span class="type">Observable</span>.from(times)</span><br><span class="line">            .flatMap &#123; item <span class="keyword">in</span></span><br><span class="line">                <span class="keyword">return</span> <span class="type">Observable</span>.of(<span class="type">Int</span>(item[<span class="string">&quot;value&quot;</span>]<span class="operator">!</span>))</span><br><span class="line">                    .delaySubscription(<span class="type">Double</span>(item[<span class="string">&quot;time&quot;</span>]<span class="operator">!</span>),</span><br><span class="line">                                       scheduler: <span class="type">MainScheduler</span>.instance)</span><br><span class="line">            &#125;</span><br><span class="line">            .debounce(<span class="number">0.5</span>, scheduler: <span class="type">MainScheduler</span>.instance) <span class="comment">//只发出与下一个间隔超过0.5秒的元素</span></span><br><span class="line">            .subscribe(onNext: &#123; <span class="built_in">print</span>(<span class="variable">$0</span>) &#125;)</span><br><span class="line">            .disposed(by: disposeBag)</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>

<p>运行结果如下：</p>
<p><a target="_blank" rel="noopener" href="https://www.hangge.com/blog/cache/detail_1933.html#"><img src= "" data-lazy-src="https://www.hangge.com/blog_uploads/201801/2018012619521911097.png" alt="原文:Swift - RxSwift的使用详解9（过滤操作符：filter、take、skip等）"></a></p>
</article><div class="post-copyright"><div class="post-copyright__author"><span class="post-copyright-meta">文章作者: </span><span class="post-copyright-info"><a href="mailto:undefined">Albert Yuan</a></span></div><div class="post-copyright__type"><span class="post-copyright-meta">文章链接: </span><span class="post-copyright-info"><a href="https://yllove.gitee.io/2021/09/17/RxSwift/RxSwift%E7%9A%84%E4%BD%BF%E7%94%A8%E8%AF%A6%E8%A7%A39-%E8%BF%87%E6%BB%A4%E6%93%8D%E4%BD%9C%E7%AC%A6/">https://yllove.gitee.io/2021/09/17/RxSwift/RxSwift%E7%9A%84%E4%BD%BF%E7%94%A8%E8%AF%A6%E8%A7%A39-%E8%BF%87%E6%BB%A4%E6%93%8D%E4%BD%9C%E7%AC%A6/</a></span></div><div class="post-copyright__notice"><span class="post-copyright-meta">版权声明: </span><span class="post-copyright-info">本博客所有文章除特别声明外，均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" target="_blank">CC BY-NC-SA 4.0</a> 许可协议。转载请注明来自 <a href="https://yllove.gitee.io" target="_blank">Albert Yuan's Blog</a>！</span></div></div><div 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